On the "My Account" part of "My Sprint" (the initial starting page of Sprint.com once you have logged in), look for a section called, "About my devices". In that section will be a little blurb with your phone number, the user name for your line, and the sort of phone you have, included in that will be a "See All Usage".
In the next screen, it will display your usage and under the Minutes, it will have blue link in small text that says, "see call log". This will display any unbilled calls. Any calls from previous bills, will have to be accessed through the Billing section and can be done so by viewing previous months bills.
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